For some buyers who have just entered the LED industry, they pay more attention to brightness and price when purchasing LED lamps, but ignore another important factor–LED Drivers. Actually, the core component of LED lamps is the LED driver, which is responsible for the safety and life cycle of LED lamps.
LED Driver including isolated driver and non-isolated driver. Then how should we choose a matched driver for LED Light?
Under normal circumstances, it is recommended to use isolated drivers from the perspective of safe use; however, if the purchaser or end user has no safety issues and prefers a more economical solution, it is recommended to use non-isolated drivers.
In this article, I will introduce the relevant knowledge of isolated led drivers and non-isolated led drivers for your reference. It contains 3 parts:
Definition of LED isolated driver and non-isolated driver
The pros and cons of LED isolated driver and non-isolated driver
How to choose a LED Light driver?
1.Definition of LED isolated driver and non-isolated driver
- Isolated Driver
It refers to the electrical connection between the input and output through a transformer, the transformer is used to reduce the high-voltage voltage to a lower voltage, and rectify it to a DC output. There is no direct connection between the primary coil and the secondary coil, so there is no danger of electric shock. In the power supply topology, there are mainly various flybacks with isolation transformers, forward excitation, half bridge, LLC, etc.
- Non-isolated Driver
The input power is directly applied to the load after step-down, the input and output are directly connected through electronic components. The input and working voltage are not isolated. When in contact with the human body, it is prone to electric shock hazard. In the power topology, non-isolated power supplies mainly include Buck, Boost, Buck-Boost and so on.
2. The pros and cons of LED isolated driver and non-isolated driver
Both isolated driver and non-isolated driver are widely used in led lights. From its definition, we can see their differences. Then How to distinguish different power supply types for novices.
The easiest way to distinguish is to look at the size, parameters, and price, as well as differences in efficiency, stability, and safety which are more specific for engineers.
Volume Non-isolated drivers are generally small in size. In order to reduce transformers, the minimum material design framework is used to achieve the same product functions.
Price The price of an isolated driver is higher than that of a non-isolated driver. Due to the lack of transformers and lower cost prices, non-isolated power supplies are mainly used in more economical types of lamps, widely acceptable in areas where they pay attention to cost. The cost of isolated drive power is high, but its stability and safety are high,which are very popular in the high-end market.
Parameters Non-isolated led drivers have a large power range and a wide voltage range, while isolated led drivers have a small power range and a much narrower voltage range.
Stability The non-isolated led driver is worse than the isolated power supply. The reason is that the non-isolated circuit design is very sensitive to surges and shocks. The instability and instability of the state grid causes the LED chip to be overloaded and damaged. In order to solve this problem, a varistor is essential in the design of a non-isolated LED drive circuit. Compared with non-isolated power supplies, isolated LED drivers are safer due to the MOS protection in the circuit design.
Safety Isolated the led driver means that the input and output terminals are electrically connected through a transformer. The conversion process of the transformer is: electromagnetic-electricity, not grounded, so there is no danger of electric shock; non-isolated driver in power circuit that is directly added to the LED load through the input and output through the electronic components, there is a risk of electric shock.
Efficiency Non-isolated LED Driver uses electronic equipment to lower the voltage. Due to the avoidance of transformer losses, the power efficiency of non-isolated LED drivers is higher than that of isolated LED drivers. The electrical efficiency of non-isolated LED drivers can reach 90%, while the efficiency of isolated power supplies using transformers is 86-88%.
A simple chart for easy understanding about pros and cons of led drivers.
3. How to choose a LED light driver?
Explain a misunderstanding at first: Many people think that the isolated LED driver must be better than the non-isolated LED driver, because the isolated LED driver is more expensive, and the expensive one is definitely better than the cheap one. This is not the case.
For LED lights, how to choose a matching LED light driver?
Our suggestion is based on different power and product characteristics.
A.High-power LED lights generally need to use isolated LED drivers. In this case, you must not use a non-isolated power supply in order to save a little cost, otherwise there will be a great potential safety hazard, and the gain is not worth the loss.
B. For low-power LED lights, whether the LED driver is isolated or non-isolated depends on the specific situation.Of course, it is good to use an isolated led driver, but there are at least two conditions, one is cost, and the other is heat dissipation. For isolated power supplies, these two issues are a test.
Which occasions are non-isolated drivers suitable for?
In many cases, non-isolated power supplies can also be used. It is very effective in many situations. The applicable occasions of non-isolated LED driver are as follows:
First,it is the indoor LED lighting environment. This kind of indoor electricity environment is better and the impact of surge is small.
Second,in high-voltage and low-current circuits. It is meaningless to use non-isolation for low voltage and large current, because the efficiency of low voltage and large current non-isolation is not higher than that of isolation, and the cost is not low.
Third,used in situations where the voltage is relatively stable, so safety can be more assured.
In fact, when we are producing LED Lights, Bullx Lighting has adopted the most suitable design plan, not the most expensive plan, in order to achieve the greatest cost performance, which can be widely used in the market.
For LED Street Light, LED Floodlight and LED Highbay Light , such big power items, we adopted Isolated Driver. Meanwhile non-isolated led drivers are widely used in led downlight, led tube, panel light which are widely accepted by customers around the world.